Mammillaria luethyi forma cristata

Notes: The defasciation is a process
leading to longitudinal cleavage of a linear crest, rather to the
complete division of the stem into individual normal shoots. Crests may
remain at any stage for a long time. But at the stage of brain-shaped
crest when the curves begin to crowd defasciation occurs rather often.
That is the linear meristem turns into a number of small apical
meristems that form normal shoots. More seldom defasciation occurs
without any reason at an earlier stage of the development of the crest.